I recently had some Holga camera shots developed(for a very hefty price I must say) and I tweaked the colours in Photshop for some, to display online.
I dont always do it with my digital shots but when I do, I always feel like Im cheating by doing it.

It isn't cheating if it improves the image, but I have seen photos that have been photoshoped to death, and looked like something that could never be captured in camera. This is what I don't like about digital manipulation.

Sometimes I find that scanned photos just don't look like the originals so I'll try to edit it to look like the original. I feel going to drastic measures like in the photos that Armageddon posted is definitely cheating.